Oil-in-water-type emulsion composition, method for producing same, and use of same

Abstract

Provided is an oil-in-water-type emulsion composition which can be produced by directly emulsifying an organopolysiloxane having a high polymerization degree, contains substantially no oversized particle, and has a small average particle size. A method for producing the oil-in-water-type emulsion composition using a vertical batch mixer is also provided. The oil-in-water-type emulsion composition is an emulsion comprising (A) an organopolysiloxane having an overall viscosity of 1,000,000 mPa·s or more or having plasticity or a mixture thereof, (B) a surfactant, and (C) water. Component (A) is emulsified in water by the action of component (B), the average particle size of emulsion particles falls within the range from 0.1 to 7.5 μm, and the content of emulsion particles each having a particle size 10 times or more larger than the average particle size is less than 5.0 vol %.

The invention claimed is: 
     
       1. A method for producing an oil-in-water emulsion composition comprising:
 (A) 100 parts by mass of an organopolysiloxane having a viscosity at 25° C. of at least 1,000,000 mPa·s or having plasticity or a mixture thereof; 
 (B1) 0.1 to 30 parts by mass of at least one non-ionic surfactant; and 
 (C) 100 to 2,000 parts by mass of water;
 the method comprising mechanically emulsifying component (A) using component (B1) in component (C) using a vertical batch mixer; 
 
 wherein;
 the vertical batch mixer is a concentric multiple shaft vertical batch mixer having multiple rotating shafts arranged along the same shaft core, and comprising a ribbon-shaped stirring blade arranged on at least one rotating shaft and a non-ribbon-shaped stirring blade arranged on a rotating shaft different from this rotating shaft; and 
 
 wherein;
 component (A) is emulsified in water by component (B1) to obtain an emulsion, 
 component (B1) is the only surfactant used to produce the oil-in-water emulsion composition and component (B1) comprises polyoxyethylene lauryl ethers; 
 the average particle size of the emulsion particles measured using the laser diffraction/scattering method is in a range from 0.1 to 7.5 μm, 
 the amount of emulsion particles having a particle size of at least 10 times the average particle size in the particle size distribution of the emulsion is less than 5.0% by volume, and 
 the apparent viscosity at 25° C. of the oil phase constituting the emulsion particles is at least 1,000,000 mPa·s or has plasticity. 
 
 
     
     
       2. The method for producing an oil-in-water emulsion composition according to  claim 1 , wherein component (A) is selected from:
 (A1) an organopolysiloxane having a viscosity at 25° C. of at least 1,000,000 mPa·s or having plasticity; or 
 (A2) an organopolysiloxane mixture having a viscosity at 25° C. of at least 1,000,000 mPa·s or having plasticity. 
 
     
     
       3. The method for producing an oil-in-water emulsion composition according to  claim 1 , wherein component (A) is an organopolysiloxane having a viscosity at 25° C. of at least 2,500,000 mPa·s or having plasticity or a mixture thereof. 
     
     
       4. The method for producing an oil-in-water emulsion composition according to  claim 1 , wherein the sum of the amount of the siloxane oligomers having a siloxane degree of polymerization of 3 to 6 in the oil phase constituting the emulsion composition is less than 1.0% by mass. 
     
     
       5. A cosmetic ingredient comprising the oil-in-water emulsion composition produced by the method according to  claim 1 . 
     
     
       6. A cosmetic comprising the oil-in-water emulsion composition produced by the method according to  claim 1 . 
     
     
       7. A film-forming agent comprising the oil-in-water emulsion composition produced by the method according to  claim 1 . 
     
     
       8. A coating or coating composition comprising the oil-in-water emulsion composition produced by the method according to  claim 1 . 
     
     
       9. A fiber-treating agent comprising the oil-in-water emulsion composition produced by the method according to  claim 1 . 
     
     
       10. The method for producing an oil-in-water emulsion composition according to  claim 1 , comprising:
 step 1) adding at least some of component (B1) to component (A) and mixing; and 
 step 2) adding at least some of component (C) to the mixture from step 1) and inverting the phase to an oil-in-water emulsion using mechanical force; and optionally 
 step 3) adding more of component (C) to the emulsion composition from step 2) to dilute the aqueous phase while stirring using mechanical force. 
 
     
     
       11. The method for producing an oil-in-water emulsion composition according to  claim 10 , comprising adding the remaining component (B1) and optionally other components in step 2) and step 3). 
     
     
       12. The method for producing an oil-in-water emulsion composition according to  claim 1 , wherein the method is a direct emulsification method using the vertical batch mixer that does not involve an emulsion polymerization reaction. 
     
     
       13. The method for producing an oil-in-water emulsion composition according to  claim 1 , wherein the amount of component (B1) used is in a range from 0.5 to 15 parts by mass per 100 parts by mass of component (A). 
     
     
       14. The method for producing an oil-in-water emulsion composition according to  claim 1 , wherein the oil-in-water emulsion is free of a silicone polyether surfactant. 
     
     
       15. The method for producing an oil-in-water emulsion composition according to  claim 1 , wherein component (B1) consists of:
 i) a first polyoxyethylene lauryl ether which is prepared from lauryl alcohol and 4 moles of ethylene oxide; and 
 ii) a second polyoxyethylene lauryl ether which is prepared from lauryl alcohol and 23 moles of ethylene oxide.